BMW e90 330d questions

[Bmwok44]

Just brought a 55 plate e90 330d and have a few questions:

1. It is slow to crank when cold. I push the start button and it is a weak crank then the car stats. Runs absolutely fine after this and no problem with idling etc, is this likely to be a battery thing?

2. The car has had a moderate remap. Whilst in gear at very low rpm, when I put my foot on the floor the car has a slight rumbling noise from the middle of the car. If I’m accelerating in the (proper gear) this noise doesn’t exist. Anything to worry about?

Thanks for the help!

[helix402]

1. Probably needs a new battery

2. Probably nothing to do with the remap. Start with basics. Tyre out of shape, bent wheel, tyre/wheel out of balance

Next step, consider prop centre bearing, rubber bit where prop joins gearbox, flywheel.

[Bmwok44]

Thanks, definitely not something to do with tyres, I’ll have a look into the other stuff.

In terms of a new battery, stupid question but this won’t affect the remap I take it?

[helix402]

New battery won’t affect remap. 55 will be pre ibs too so no batt registration needed.